US Secretary of State Antony Blinken landed in Tel Aviv on Thursday as part of a Middle East tour to show Washington's solidarity with Israel after the attacks by Palestinian Hamas militants and to work to prevent the conflict from widening.

Blinken will also try to help secure the release of hostages kidnapped by Hamas — some of whom are Americans — and advance talks with Israelis and Egyptians on providing a safe passage of Gaza civilians out of the enclave before a possible Israeli ground invasion.

After Israel, Blinken will head to Jordan, where he will meet with King Abdullah and Palestinian Authority President Mahmoud Abbas.

Blinken's trip comes as Israel has unleashed the most powerful bombing campaign in the 75-year history of its conflict with the Palestinians, vowing to annihilate the Hamas movement that rules the Gaza Strip in retribution for the attacks.

Israel has put Gaza under siege to stop food and fuel reaching the enclave of 2.3 million people.

A senior State Department official, speaking to reporters on the condition of anonymity, said Washington was working to advance talks on providing a safe passage to civilians, including Americans in Gaza.

"There's a community of something in the order of 500 to 600 Palestinian Americans, more or less, resident in Gaza. Some of them want to leave...and we are working to organize safe passage," the official said.

The United States is talking "intensively" with Israeli and Egyptian governments to help arrange that, the official said.

Another priority for Blinken will be to convey a message of deterrence to Iran and any Iran-backed groups to avoid getting involved in the conflict.

"We're very intent on demonstrating through this visit and through the onward visits that we're committed to keeping other parties out of this conflict," the official said.

U.S. President Joe Biden, speaking to Jewish community leaders in Washington on Wednesday, said the deployment of U.S. warships and aircraft closer to Israel should be seen as a signal to Iran, which backs Hamas and Lebanon's Hezbollah movement.

"We made it clear to the Iranians: Be careful," Biden said.